(Thu Nov 20 2008 00:00:00 GMT+0200 (Eastern European Standard Time)) Supposedly people who imbibe mercury become crazy as, well, a madhatter (so named because old-style hat-making practices involve the use of mercury). So maybe it sounds crazy to talk about multiple heads but in this case the mercury is the Mercurial source code management system. In Mercurial a 'head' is the endpoint of a chain of changes and it becomes downright inconvenient when there are multiple endpoints in the chain of changes in your source repository.
